Electrical attachment



Jan. 1935- B. F. MULDOON ELECTRI CAL ATTACHMENT 2 Shets-Sheet 1 Filed July 14. 1930 INVENTOR .Baz iardlfilzldmn.

Jan. 8, 1935.

B. F. MULDOON ELECTRICAL ATTACHMENT Filed July 14," 1930 2 Sheets-Sheet2 Patented Jan. 8, 1935 UNITED STATES PATENT OFFICE ELECTRICAL anacmmvr Bernard F. Muldoon, Monntainview, N. 1., as-

signor to Henry Hyman. New York, N.

Application July 14,1939, Serial No. 467,759

6 Claims. (CL 173-354) chain.

The novel features of the invention will be best understood from the following description and the annexed drawings. in which I have shown selected embodiments of the invention, and in which:--. v

Fig. 1 is an elevation of an attachment constructed according to one form of the invention;

Fig. 2 is a vertical section through the attachment shown in Fig. 1, and taken on a plane parallel to the plane of Fig. 1;

Fig.3 is a section on the line 9-3of Fig. 2;

Fig. 4isasectionontheline4-4ofFig.2;

Fig. 5 is a view showing the interior construction of the two parts of the casing of the attachment:

Fig. '6 is a perspective view of one of the conducting members or strips; v

' Fig. 7 is a view similar toFig. 1, but showing a different embodiment of the invention;

Fig. 8 is a view similar to Fig. 2,-but showing the embodiment appearing in Fig. 7;

Fig. 9 is a section on the line 9-9 of Fig. 8; Fig. 10 is a view similar to Fig. 5, but showing the embodiment .of Fig. '1;

. Fig. 11 is a perspective view of a conductor used in this embodiment;

Fig. 12 is a perspective view of a detail. Referring first to Figs. 1 to 6, inclusive, I have shown therein an attachment forming what is commonly known in the trade as a socket attach- V ment, and which comprises an elongated casing 1 formed in two parts2 and 3. These parts are preferably made of insulating material and are secured together by means of a single bolt 4 having the head and ,nut thereof received in recesses in the two parts as plainly shown in Fig. 3.

The upper portion of the attachment is formed into a neck on which is placed a threaded metallic member 5 which forms the side contact when screwed into-a socket such as an ordinary electric light flxture. The center contact, when the attachment is in place, is shown at 6, and this contact is preferably a part of a strip '1 of metal and forming a conductor extending lengthwise of the casing. It will be seen that the casing is hollow and has therein a chamber 8 to contain switch operating mechanism which will be referred to later.

The walls of the casing meet on a plane as shown at 9, and the contacting faces of the walls are provided with grooves which are preferably matched and which are so formed as to receive the conductors leading to the switch operating mechanism and parts associated therewith and to thus insulate the conductors where such in sulation is necessary.

Referring now more particularly to Figs. 2, 4, and 5, it will be seen that the conductor '1 is disposed in a groove 10 in a wall of the part 3 and in a groove 10' which is formed in the part 2 in. such a way that the grooves 10 and 10' match 'when the parts-are assembled. The strip '7 extends outwardly through matching grooves 11 and 11' to form the contact 6, and then is bent inwardly again into grooves 12 and 12', as shown at 18 in Fig. 2.

The floor 14 of the chamber 8 is formed by transverse members 15 and 16 in the parts 2 and 3 respectively, and disposed on this floor is a base plate 1'! of insulating material. The base plate, as best shown in Figs. 4 and 12, is noncircular in contour, as is also the cross section of the chamber, and therefore the plate is prevented from rotation in the chamber. On this base plate is disposed the switch and the switch operating mechanism. The switch is here shown as one of the ratchet type and includes ratchet teeth 18 formed integral with the base plate and extending upwardly therefrom. Two opposite ratchet teeth are covered respectively by contacts 19 and 20.

The contact 20 may be secured to the base plate by a rivet 21, which may also conveniently be used to secure to the base plate a contact 22 which forms a central contact for a socket 23 in the lower end of the casing. This socket is of the usual metallic screw-threaded type.

The contact 19 is provided with downwardly extending ears 24 received in slots extending inwardly from the edge of the base plate, and the lower ends of the ears may be bent against the underside of the base plate. In this way, the 7 wall of the chamber prevents side displacement of the contact 19. In this particular illustration, the contact has an extension which forms a contact 25 engaging with the conductor 7.

Extending upwardly from the base plate, is a stud 26, the head 27 of which engages the roof 28 of the chamber 8, and thus the stud is held in place and acts against the base plate to prevent upward movement thereof. The roof 28 is formed by matching transverse members 29 and 30 on the parts 2 and 3 respectively. A spring 31 surrounds the stud and forms part of the switch operating mechanism which will not be described in more detail, because it is not necessary to do so for an understanding of this invention.

In the wall of the casing on the plane 9 is formed a hole 32 through which passes a chain 33 for operating the switch mechanism. The faces on the parts 2 and 3 which meet on this side of the casing at the plane 9 are likewise formed with matching grooves to receive a conductor 34.

The upper end of this conductoris bent outwardly through an opening 35 to engage the side contact 5. The grooves 36 in which the conductor 34 is received and which are locatedin the part 3 terminate on opposite sides of the hole 32 (Fig. 5), the ends 37 of these grooves being separated from the hole by a thickness of insulating material which serves to insulate the conductor from the chain passing through the hole. This construction is plainly shown in Figs. 2 and 5. The conductor 34, as best shown in Fig. 6, is arched at 38, and this arched portion is disposed in a depression 39 in the groove 40 which matches the grooves 36. This depression is of greater depth than the width of arch 38, so thatthe chain running through the hole 32 will engage the top walls 01' the depression, and the depth of the depression prevents the chain from coming in contact with the arch 38.

The ends 39' or the arch are received in th grooves 36 adjacent the ends 3'7 thereoi. The conductor 34 is extended downwardly past the hole 32 and engages a tongue 23' extending upwardly from the socket 23 and disposed in the lower groove 36.

The fioor 15 and the base plate 17 are provided with matching grooves, as plainly shown in Fig. 2, and these matching grooves form a hole for receipt of the bolt 4. By this arrangement, the bolt is properly insulated from mechanism within the casing without the sacrifice 01' other material.

, Referring now to Figs. '7 to 11, inclusive, I have shown therein a diflerent embodiment of the invention. In this form, the casing is made in two parts 2' and 3', and a metallic socket 23 is disposed in the lower end of the casing as before. Switch operating mechanism is received in the chamber 8 as in the other forms, and this mechanism is operated by the chain 33. Similarly, a conductor "I is arranged in matching grooves 10 and 10,-and a second conductor 34 is disposed in matching grooves- 36 and 40.

However, in this form, each of the parts 2' and 3' is provided with blade sockets, each socket comprising a pair of apertures 41 into which blades on a plug or the like may be inserted and come into engagement with contacts 42. In this form, these contacts are formed on strips 43 which are secured to the conductor 34, the conductor in this form being secured directly to the socket 23. The opposite parts 0! the casing are provided with matching recesses 44 in which the contacts 42 are received. In this form, the bolt 45 is passed through the fioor 46 of the chamber 8, this floor being provided with a hole 47 for that purpose. In this embodiment, the fioor is made much thicker than in the previously describedembodiment in order to provide space for the recesses 44 to receive the contacts 42.

I claim:

1. An electrical attachment comprising a casing of insulating material in two substantially equal parts, switch mechanism within said casing, a chain adapted to operate said mechanism, said casing having a hole through which said chain passes, said hole being split by the dividing plane between said parts, and an electrical conductor in the form of a strip extending past said hole and received in matching grooves in the twoparts, said conductor being provided with an arched portion extending around said hole and beyond the wall thereof.

2. An electrical attachment comprising a casing 1,9so,ses

of insulating material formed of two substantially equal parts, switch mechanism within the casing, a member adapted to operate said mechanism and extending through a hole in the casing, said hole being disposed on the dividing plane between the parts, means forming matching grooves in the walls of the two parts adjacent said hole, a wall of insulating material disposed between said hole and the groove in one part, the groove in the other part having a depression around said hole,

.and a strip conductor disposed in said grooves when the parts are assembled, said strip at said hole being disposed in said depression, and the depression being thicker than the width oi the conductor.

3. An electrical attachment comprising a casing of insulating material formed of two substantially equal parts, switch mechanism within the casing, a member adapted to operate said mechanism and extending through a hole in the casing, said hole being disposed on the dividing plane between the parts, the walls of the two parts adjacent said hole having matching grooves therein, a wall of insulating material disposed between said hole having matching grooves therein and the groove in one part, the groove in the other part having a depression around said hole, and a strip conductor disposed in said grooves when the parts are assembled, said strip at said hole being disposed in said depression, and the depression being thicker than the width of the conductor, said strip being cut away to form an arch around said hole.

4. An electrical attachment comprising an elongated casing formed in two parts, the walls of said casing forming. a chamber, switch mechanism disposed in said chamber and comprising a base plate of insulating material, said chamber being non-circular in cross' section, and the base being of similar contour to fit the chamber and thus prevent rotation therein, and a contact member mounted above said base and having ears received in slots extending from one side 01 the base whereby movement of the ears out oi said slots is prevented by the adjacent wall oi! the chamber.

5. An electrical attachment comprising an elongated casing formed in two parts, the walls of said casing forming a chamber, switch mechanism disposed in said chamber and comprising a base plate 01' insulating material, said chamber being non-circular in cross section, and the base being of similar contour to fit the chamber and thus. prevent rotation therein, a contact member mountedabove said base and having ears received in slots extending from one side of the base whereby movement of the ears out of said slots is prevented by the adjacent wall of the chamber, and a conductor extending lengthwise oi. the casing and engaging said contact.

6. An electrical attachment comprising an elongated casing formed in two parts, the walls of said casing forming a chamber, switch mechanism disposed in said chamber and comprising a base plate of insulating material, means preventing rotation of said base plate in said chamber and a contact member mounted above said base plate and having ears received in slots extending from one side of the base, said side of base being disposed adjacent a wall of the chamber whereby movement of' the ears out of said slots is prevented by said wall.

BERNARD F. MULDOON. 

